/*
* Careful here! We test whether the file pointer is NULL before
* releasing the fd. This ensures that one clone task can't release
* an fd while another clone is opening it.
*/
SYSCALL_DEFINE1(close, unsigned int, fd)
{
struct file * filp;
struct files_struct *files = current->files;
struct fdtable *fdt;
int retval;
spin_lock(&files->file_lock);
fdt = files_fdtable(files);
if (fd >= fdt->max_fds)
goto out_unlock;
filp = fdt->fd[fd];
if (!filp)
goto out_unlock;
rcu_assign_pointer(fdt->fd[fd], NULL);
__clear_close_on_exec(fd, fdt);
__put_unused_fd(files, fd);
spin_unlock(&files->file_lock);
retval = filp_close(filp, files);
/* can't restart close syscall because file table entry was cleared */
if (unlikely(retval == -ERESTARTSYS ||
retval == -ERESTARTNOINTR ||
retval == -ERESTARTNOHAND ||
retval == -ERESTART_RESTARTBLOCK))
retval = -EINTR;
return retval;
out_unlock:
spin_unlock(&files->file_lock);
return -EBADF;
}
SYSCALL_DEFINE1(close, unsigned int, fd)
{
struct file * filp;
struct files_struct *files = current->files;
struct fdtable *fdt;
int retval;
spin_lock(&files->file_lock);
fdt = files_fdtable(files);
if (fd >= fdt->max_fds) {
pr_debug("[%s] fd %u exceeds max_fds %u (user: %s %d:%d)\n",
__func__, fd, fdt->max_fds,
current->comm, current->tgid, current->pid);
goto out_unlock;
}
filp = fdt->fd[fd];
if (!filp) {
struct fdt_user* user = &fdt->user[fd];
if (unlikely(user->remover && user->remover != current->pid)) {
struct task_struct* task = find_task_by_vpid(user->remover);
pr_warn("[%s] fd %u of %s %d:%d is"
" already closed by thread %d (%s %d:%d)\n",
__func__, fd,
current->comm, current->tgid, current->pid,
user->remover,
task ? task->comm : "<unknown>",
task ? task->tgid : -1,
task ? task->pid : -1);
}
goto out_unlock;
}
#ifdef CONFIG_HTC_FD_MONITOR
if (in_fd_list(fd, 0) == 1) {
printk("fd error: %s(%d) tries to close fd=%d illegally\n", current->comm, current->pid, fd);
force_sig(SIGABRT, current);
spin_unlock(&files->file_lock);
force_sig(SIGABRT, current);
return 0xBADFD;
}
#endif
rcu_assign_pointer(fdt->fd[fd], NULL);
fdt->user[fd].remover = current->pid;
__clear_close_on_exec(fd, fdt);
__put_unused_fd(files, fd);
spin_unlock(&files->file_lock);
retval = filp_close(filp, files);
if (unlikely(retval == -ERESTARTSYS ||
retval == -ERESTARTNOINTR ||
retval == -ERESTARTNOHAND ||
retval == -ERESTART_RESTARTBLOCK))
retval = -EINTR;
return retval;
out_unlock:
spin_unlock(&files->file_lock);
return -EBADF;
}
/*
* Careful here! We test whether the file pointer is NULL before
* releasing the fd. This ensures that one clone task can't release
* an fd while another clone is opening it.
*/
SYSCALL_DEFINE1(close, unsigned int, fd)
{
struct file * filp;
struct files_struct *files = current->files;
struct fdtable *fdt;
int retval;
#ifdef CONFIG_SEC_DEBUG_ZERO_FD_CLOSE
if (fd == 0 && strcmp(current->group_leader->comm,"mediaserver") == 0)
panic("trying to close fd=0");
#endif
spin_lock(&files->file_lock);
fdt = files_fdtable(files);
if (fd >= fdt->max_fds)
goto out_unlock;
filp = fdt->fd[fd];
if (!filp)
goto out_unlock;
rcu_assign_pointer(fdt->fd[fd], NULL);
__clear_close_on_exec(fd, fdt);
__put_unused_fd(files, fd);
spin_unlock(&files->file_lock);
retval = filp_close(filp, files);
/* can't restart close syscall because file table entry was cleared */
if (unlikely(retval == -ERESTARTSYS ||
retval == -ERESTARTNOINTR ||
retval == -ERESTARTNOHAND ||
retval == -ERESTART_RESTARTBLOCK))
retval = -EINTR;
return retval;
out_unlock:
spin_unlock(&files->file_lock);
return -EBADF;
}
static int task_get_unused_fd_flags(struct shfile_proc *proc, int flags)
{
struct files_struct *files = proc->files;
int fd, error;
struct fdtable *fdt;
unsigned long rlim_cur;
unsigned long irqs;
if (files == NULL)
return -ESRCH;
error = -EMFILE;
spin_lock(&files->file_lock);
repeat:
fdt = files_fdtable(files);
fd = find_next_zero_bit(fdt->open_fds, fdt->max_fds, files->next_fd);
/*
* N.B. For clone tasks sharing a files structure, this test
* will limit the total number of files that can be opened.
*/
rlim_cur = 0;
if (lock_task_sighand(proc->tsk, &irqs)) {
rlim_cur = proc->tsk->signal->rlim[RLIMIT_NOFILE].rlim_cur;
unlock_task_sighand(proc->tsk, &irqs);
}
if (fd >= rlim_cur)
goto out;
/* Do we need to expand the fd array or fd set? */
error = expand_files(files, fd);
if (error < 0)
goto out;
if (error) {
/*
* If we needed to expand the fs array we
* might have blocked - try again.
*/
error = -EMFILE;
goto repeat;
}
__set_open_fd(fd, fdt);
if (flags & O_CLOEXEC)
__set_close_on_exec(fd, fdt);
else
__clear_close_on_exec(fd, fdt);
files->next_fd = fd + 1;
#if 1
/* Sanity check */
if (fdt->fd[fd] != NULL) {
printk(KERN_WARNING "get_unused_fd: slot %d not NULL!\n", fd);
fdt->fd[fd] = NULL;
}
#endif
error = fd;
out:
spin_unlock(&files->file_lock);
return error;
}